executor: fix The JSON Data can not import to TiDB correctly by load data (#21043)

[ti-srebot]

cherry-pick #21043 to release-4.0

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What problem does this PR solve?

Issue Number: close #20136

Problem Summary:

What is changed and how it works?

What's Changed:

change load data reader

How it Works:

load data will consistent with mysql

Related changes

Check List

Tests

• Manual test (add detailed scripts or steps below)

> cat load_json.csv
"aaa"
"{""itemRangeType"":0,""itemContainType"":0,""shopRangeType"":0}"
"{""itemRangeType"":0,""itemContainType"":0,""shopRangeType"":1,""shopJson"":""[{\""id\"":\""A1234\"",\""shopName\"":\""AAAAAA\""}]""}"
"{""itemRangeType"":0,""itemContainType"":0,""shopRangeType"":1,""shopJson"":""[{\""id\"":\""A1234\"",\""shopName\"":\""AAAAAA\""}]""}"

mysql> drop table if exists load_json;
Query OK, 0 rows affected, 1 warning (0.01 sec)

mysql> CREATE TABLE `load_json` ( `aaa` VARCHAR ( 2000 ) );
Query OK, 0 rows affected (0.00 sec)

mysql> load data local infile '/data/load_json.csv' ignore  into table load_json columns terminated by ',' enclosed by '"' escaped by '' ignore 1 lines (`aaa`); 
Query OK, 3 rows affected (0.01 sec)
Records: 3  Deleted: 0  Skipped: 0  Warnings: 0

mysql> select * from load_json; 
+---------------------------------------------------------------------------------------------------------------------+
| aaa                                                                                                                 |
+---------------------------------------------------------------------------------------------------------------------+
| {"itemRangeType":0,"itemContainType":0,"shopRangeType":0}                                                           |
| {"itemRangeType":0,"itemContainType":0,"shopRangeType":1,"shopJson":"[{\"id\":\"A1234\",\"shopName\":\"AAAAAA\"}]"} |
| {"itemRangeType":0,"itemContainType":0,"shopRangeType":1,"shopJson":"[{\"id\":\"A1234\",\"shopName\":\"AAAAAA\"}]"} |
+---------------------------------------------------------------------------------------------------------------------+
3 rows in set (0.00 sec)

Side effects

• Performance regression
  • Consumes more CPU
    No
  • Consumes more MEM
    No
• Breaking backward compatibility
  No

Release note

• fix The JSON Data can not import to TiDB correctly by load data

[ti-srebot]

/run-all-tests

[ti-srebot]

@ti-srebot you're already a collaborator in bot's repo.

[lzmhhh123]

LGTM

[SunRunAway]

LGTM

[SunRunAway]

/merge

[ti-srebot]

Your auto merge job has been accepted, waiting for:

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[ti-srebot]

/run-all-tests

[ti-srebot]

@ti-srebot merge failed.

[ichn-hu]

/run-all-tests

[ichn-hu]

/run-all-tests

[SunRunAway]

/merge

[ti-srebot]

Your auto merge job has been accepted, waiting for:

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[ti-srebot]

/run-all-tests